This invention relates to improved immunoassays of psychotomimetic drugs, narcotic drugs, tetrahydrocannabinols and other psychoactive drugs.
At the present time, there are certain methods used for the determination of psychotomimetic and narcotic drugs in biological materials.
The techniques that are used in the present time for the determination of drugs in biological materials, are described in detail in the Handbook of Analytical Toxicology (Irving Sunshine, Editor; The Chemical Rubber Company, Publisher; Cleveland, OH, 1969). They include in different combination for the different drugs: paper, thin layer and gas-liquid chromatographic methods, crystal tests, fluorescence, infrared, ultraviolet, thermal microscopy and animal pharmacology studies.
In general, the tests are time consuming, expensive, require expensive equipment, and require well trained personnel. Some of the tests are not sensitive, others lack high specificity. Special difficulty is encountered in the determination of one drug in the presence of other drugs in the same biological material specimen. Thus heroin is difficult to determine in the urine in the presence of nicotine, as disclosed by D.J. Berry et al in "The Detection of Drugs of Dependence in Urine" (Bulletin on Narcotics 22, No. 3, July-September 1970; United Nations Publication). Tetrahydrocannabinols are difficult to determine in the presence of barbiturates, and complicated methods are needed for their determination in the presence of barbiturates, as described by Harold V. Street in "Identification of Drugs by a Combination of Gas-Liquid, Paper and Thin-Layer Chromatography" (Journal of Chromatography 48, 291-4, 1970).
The methods of the present invention have the advantages of simplicity, speed, specificity and low cost. They also have the advantage of being able to be applied "on the spot" (e.g. emergency room of a small field hospital). Van Vunakis et al ("Production and Specificity of Antibodies Directed towards 3,4,5-Trimethoxy-phenyl-ethylamine, and 2,5-Dimethoxy-4-methylamphetamine," Bioch. Pharmacol. 18, 393-404, 1969) were able to obtain high specificity and sensitivity in their determination, by microcomplement fixation inhibition of 3,4,5-Trimethoxy-phenylethylamine and congeners, as well as 2,5-Dimethoxy-4-Methylamphetamine and congeners. Micro-complement-fixation-inhibition is however a complicated method. Reagents have to be prepared freshly for each experiment, and they require specially trained personnel. In the methods hereinafter to be described, no such limitations are present.
The length of time required by presently known procedures for determining psychoactive drugs also severely limits their usefulness in clinical applications.
The invention also includes immunological methods for the treatment of drug intoxication; the treatment and prevention of drug addiction, drug dependence and drug abuse; and the treatment of schizophrenia. The need for treatment methods for intoxication by psychoactive drugs, methods for freeing persons dependent on such drugs from their dependence, and methods of treating schizophrenia has long been felt. The present methods provide attractive and useful approaches to all of these needs.